full title of the longest of these essays is ‘The Principles which Lead and Direct Philosophical Enquiries Illustrated by the History of Astronomy’. This reveals that Smith’s true interest is not the details of the development of astronomy, but rather the exploration of the nature of philosophy (including what we would now call science). His main contention is that the formal practice of science is a deliberate version of the underlying way in which the human mind operates. Smith follows Hume’s views on the association of ideas through repeated experience as the source of the habitual mental patterns that form human understanding. As we saw above, Hume’s reputation as a sceptic arose from his view, first laid out in the Treatise of Human Nature, that the power of philosophy to provide absolute certainty for our beliefs was radically limited.
For both Hume and Smith, humans form their beliefs about the world from experience. We form expectations drawn from repeated past experience of links between phenomena and these suggest to us that a similar relationship will hold in the future. As a result, our knowledge is always a probability rather than absolutely certain. Our minds flow from one idea to another through a set of habitual expectations and associations of ideas. We think that the sun will rise tomorrow because it always has done in our past experience, that fire is hot because it has always been found to be so; but we cannot be absolutely certain that these generalizations will continue to hold. This observation colours Hume’s and Smith’s understanding of what we can expect from philosophy and leads to a sort of epistemic modesty that is characteristic of the latter’s entire career.
That said, both Hume and Smith were clear that such knowledge was reliable and that nature did provide us with universally applicable laws that could be explored through observation and theorization. The point, as Hume had observed at the start of the Treatise, was that experience and observation were the only truly reliable basis for belief. Smith seeks to explore how it is that human beings understand the world by understanding how the mind creates these regularities from its experience of the world.
Wonder, Surprise, and Admiration
At the heart of his argument is the idea that we are prompted to science not by reason, but by our emotions. Smith believed that we do not originally pursue science for the utilitarian reasons that Francis Bacon had suggested. Instead our scientific method is an extension of an emotionally driven need to understand the world. Science has its origins in our emotions; more specifically it arises from three particular emotions: ‘Wonder, Surprise, and Admiration’.4 When we come across something that we have never encountered before, we try to situate it in relation to our past experience, and when we cannot do this, it makes us uneasy.
Smith thought that this was precisely because our knowledge of the world comes in the form of habitual generalizations drawn from experience. Our understanding of things is a pattern of connections that exist in the imagination and which help to orientate us. The ‘natural career of the imagination’5 flows smoothly and allows us to make sense of the world until it comes across something that does not fit with our established mental patterns. The emotion of wonder is produced when we come across something we have never encountered before; we are surprised by the new or by the familiar appearing in an unexpected context; and we admire an explanation that is able to fit the wondrous and surprising into a coherent account of nature. Smith’s point here is that our pursuit of understanding of the world comes from a natural curiosity that is driven by our emotions.
Surprises are unsettling, they upset the smooth operation of our minds, and this uneasiness, this anxiety, is what drives us to science. Smith thinks that our first inclination is to try to account for a surprising event by fitting it into our established patterns of knowledge. If we can do this, our uneasiness dissipates. Indeed we become content and admire the way in which we have been able to place the phenomenon within a system of understanding. Smith regards this experience as both emotional (anxiety dissipating) and aesthetic (in the sense that we admire the beauty of the systematic explanation). Once someone has provided us with an explanation, we are no longer puzzled. Like someone who has seen behind the stage curtain, the special effects of the opera no longer strike us with awe – instead we admire them for the manner in which they are systematically arranged to produce the desired result. However, if we are unable to do this, we remain anxious to make sense of the phenomenon.
It is at this point that we develop more sophisticated systems of understanding. Here Smith makes a startling claim: that the first attempts to respond to the wondrous were religious. Smith provides us with an account of the development of polytheistic religion as a natural attempt to make sense of things that do not fit with established experience. Floods, lightning, famine, are made explicable by seeing them as the deliberate actions of a deity.6 The anger of a superhuman entity might seem an odd source of consolation, but it is better than something that is totally inexplicable. The psychologically unsettling impact of the inexplicable is far worse than that which is supernaturally explicable. This provides a degree of calmness to the mind as we now have some sort of explanation. Such superstitions arise from exactly the same emotional needs as science. The difference for Smith is that science becomes more successful at banishing unease than superstitious religions.
It’s important to understand why science comes to displace superstition and how Smith thought that this had happened in particular societies. First of all, he thought that certain social conditions had to be in place before a scientific method could be developed. Science is only possible when ‘order and security’7 have been secured and people have been freed from absolute want. It is only when we develop some leisure time to pursue our curiosity that we are able to recognize the order that exists in nature and to develop a conscious system of scientific inquiry to understand it. Poverty and superstition go together because the struggle to secure subsistence occupies all of our attention and leaves us ignorant. Science is also facilitated by the division of labour. A separate class of professional philosophers emerges who set their mind to observing nature and seeking its patterns. As this develops, the branches of knowledge divide and specialists develop.
Once the scientific method arises, it begins to supplant superstition precisely because it is more systematic and coherent in its ability to explain the world. In order to understand Smith’s view here and his entire understanding of the task of philosophy, it’s vital to grasp that he sees the task of religious explanations and science as the same. They try to make sense of the world and to calm the mind by banishing anxiety. The test of all such explanations is that they are able to account for what is experienced. A theory or a system of thinking must be subject to a ‘reality check’. If it fails adequately to lead our minds through the order of nature in a smooth fashion, then it will be supplanted by another account that is able to achieve this.
Philosophy is the ‘science of the connecting principles of nature’.8 Its success depends on its ability to render things ‘familiar to the imagination’.9 Smith sums up his view in the following terms:
Philosophy, by representing the invisible chains which bind together all these disjointed objects, endeavours to introduce order into this chaos of jarring and discordant appearances, to allay this tumult of the imagination, and to restore it, when it surveys the great revolutions of the universe, to that tone of tranquillity and composure, which is both most agreeable in itself, and most suitable to its nature.10
Smith’s account of the development of science is undertaken through an account of the move from one system of thought to another. For Smith, a system is an ‘imaginary machine invented to connect together in the fancy those different movements and effects which are already in reality performed’.11 A system for Smith suggests a coherent body of explanation, a theory that accounts for more than one observed phenomenon. Recognizing that there are regularities in nature is what leads humanity from the belief in a multiplicity of gods acting on their own whims to a monotheistic conception of God acting in accordance with rules of nature. One principle that explains a great many things is better at relieving our ‘anxious curiosity’12 and leading our imagination in a smooth fashion. Once we begin the self-conscious exploration of the world through observation, we begin the attempt to organize our ideas into a single coherent system,