In this essay, as the title conveys, Hobbes’s aim is to lay out and discuss the working of the human senses. It is the “thoughts of man” which Hobbes is concerned about, and there are two ways to comprehend these thoughts. First is “singly” and second is through “trayn”. Though Hobbes focuses on the former term only, we need to know what exactly he means by both the terms. The word ‘singly’ indicates single or in individual terms, while “trayn” or to be more clear ‘train’ implies a series of links and relations with others. The third chapter “Of the Consequence or Train of Imagination” deals with the second term at length.
When Hobbes considers thoughts in individual terms, it becomes nothing more than the representation or appearance of an external body/object kept away from us. This object works on different organs of our body like the eyes and the ears, producing different appearances. Here, it is remarkable that appearance does not simply mean what one sees but what one can perceive and understand through any part of his/her body. Among all appearances, the one which is primary and can be called original is sense. Nothing, as Hobbes correctly states, is comprehensible by the human mind in the absence of the senses i.e. skin, eyes, ear, nose and tongue. Everything produces a distinct conception in the human mind when the senses hit the respective organs of one’s body.
The working of the senses has been discussed thoroughly in the successive chapters “Of Imagination” and “Of the Consequence or Train of Imagination” but Hobbes has briefly talked about it here also. The cause of the sense or what stimulates one’s senses is the external object which induces the relevant organ to react to the pressure of the object, either rapidly or ponderously. It is the external body or the object which makes man sensible of it by pressing or stimulating the corresponding organ of the body to react to each pressing. Taste and touch are the instances where the respective senses respond at once, while in the case of smelling, hearing and seeing something, the reaction takes time. The object exerts pressure on the nerves and membranes of the related organs which, in turn send messages to the brain and heart to interpret them. Where, in the case of touch and taste, interpretation happens immediately; in hearing, smelling, and seeing, mediation by the nerves take time. Though he was a philosopher, Hobbes’s views here illustrate the scientific methods he seems to follow to describe the working of our senses. It also highlights the scientific advancements in his time.
Objects can be sensed, because of the continuous motion of their matter. Likewise, our senses which are pressed by the object are in constant motion, that is in a regular movement. This implies that the central cause of sense is motion, for as Hobbes has philosophised many times in his other works, the external world is nothing more than a chaotic interaction between objects, due to a series of motions. Hobbes’ materialist claims are similar to the physical sciences, which underline the fact that all activities are the result of the collision of material bodies with one another. Human beings, being part of the external and physical world, are not different from these objects and also interact with the external world through such motion. We feel and sense the presence of an object because the movement of the object interacts with our sensory organs; whereon another set of motion is unleashed within our body that ultimately ends in our brain and makes us feel the object; whether it is rough, smooth, hot, cold, quiet, or loud, and so on.
The appearance of the object is only a fancy, that is a thought or idea arising in the mind, and is not ingrained in the object. Just as we fancy a light on rubbing our eyes and hear a distinct sound on pressing the ears; so it is with the bodies we see, hear, touch, smell and taste. They also produce a fancy via their strong, though unnoticeable movements, which then aid us to sense them. It suggests that fancy is not inherent in the objects we perceive “for if those Colours, and Sounds, were in the bodies, or the Objects that cause them, they could not bee severed from them, as by glasses, and in, Ecchoes by reflection…” Hobbes proves his point by alluding to the scientific fact that had it been the case, the colours and sounds of these bodies would not have been separated from them by reflection of light through a glass and reverberation of sound. Hence, however much the fancy seems to be within the object which causes sense in us, the object is different from the fancy. Hobbes then concludes that sense is nothing but an original fancy, which is caused by the motions of the object and produces pressure on the organs for the relevant fancy.
Philosophizing the working of the senses and refuting the intrinsic presence of fancy in objects, Hobbes categorically attacks the undisputed ideas of Aristotle that were widely accepted in the universities of the Christian world. Aristotle’s ideas regarding object and fancy are just opposite of what Hobbes propounds in his essay. And this is the reason why Hobbes condemns, and is critical of the unwavering belief of such “philosophy-schools” in Aristotle’s texts. These texts argue that an object can be seen because it sends forth an “apparition,” or a ghost spirit of the object; all the time, in all directions. The same holds true for the objects heard, smelt, touched and tasted. This apparition is also called “visible shew” (or species) in case the object is being seen; “hearing shew” in case it is being heard and so on. Further, to understand something, the Aristotelian view is that objects give intelligible “shew” or “species”. Moreover, the words ‘fancy’ and ‘representation’ are associated with Aristotle, who argues that every object has an intrinsic essence and this essence can always be recognised even if the object is not available at the moment. Apparently, Hobbes disagrees with Aristotle’s claims and asserts that “the object is one thing” and the fancy or essence associated with it is another. For Hobbes, the senses operate only when they physically come in contact with the actual matter or substance, and not with the image or species of the substance which it constantly gives forth.
Hobbes dismisses the older philosophies entirely, not because he disregarded the importance of the universities but because he is determined to focus on and locate their significance in the commonwealth. This he discusses in other essays of the book. Hobbes seems to indicate that instead of sticking to given knowledge we should make attempts to advance or improve it, according to demands of the time. And therefore, towards the end of the essay, he hints at the amendments which are needed in the field of “Speech”. Speech or language is used to convey one’s mental thoughts verbally or orally. This issue has been dealt further in the fourth chapter “Of Speech”.