Non-scientific Applications
Neither is the frictionless plane a concept unique to science. Many other fields have used conceptual understandings of problems with limited or no direct real-world applicability to great effect. Of particular note is a reference to Galileo’s plane in Thomas Hobbes’ Leviathan. In Leviathan, Hobbes begins by considering the condition of man in the state of nature; without government, without morals, without order. He famously describes the state of nature as the state of war, a state of all against all, where life was solitary, poor, nasty, brutish, and short. However, Hobbes makes clear that the justification for the government described in Leviathan, whose primary purpose is to keep man out of the state of nature, and from the corresponding fear of a violent death, does not depend upon man ever having lived in this condition. Instead, just like the frictionless plane, his description of the state of nature is valuable for how it informs humanity's current condition, not only for the accuracy of its description:
"But there is another saying not of late understood, by which they might learn truly to read one another, if they would take the pains; and that is, Nosce Teipsum, Read Thy Self: which was not meant, as it is now used, to countenance, either the barbarous state of men in power, towards their inferiors; or to encourage men of low degree, to a sawcie behaviour towards their betters; But to teach us, that for the similitude of the thoughts, and Passions of one man, to the thoughts, and Passions of another,whosoever looketh into himselfe, and considereth what he doth, when he does Think, Opine, Reason, Hope, Feare, &c, and upon what grounds; he shall thereby read and know, what are the thoughts, and Passions of all other men...for these the constitution individuall, and particular education do so vary, and they are so easie to be kept from our knowledge, that the characters of mans heart, blotted and confounded as they are, with dissembling, lying, counterfeiting, and erroneous doctrines, are legible onely to him that searcheth hearts. And though by mens actions wee do discover their designee sometimes; yet to do it without comparing them with our own, and distinguishing all circumstances, by which the case may come to be altered, is to decipher without a key, and be for the most part deceived."
More recently, John Rawls, while very much disagreeing with Hobbes' conception of the state of nature, used this same methodology in describing an admittedly artificial original position from which his Theory of Justice derives.
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