WE have now not merely explored the territory of pure understanding, and carefully surveyed every part of it, but have also measured its extent, and assigned to everything in it its rightful place. This domain is an island, enclosed by nature itself within unalterable limits. It is the land of truth -- enchanting name! -- surrounded by a wide and stormy ocean, the native home of illusion, where many a fog bank and many a swiftly melting iceberg give the deceptive appearance of farther shores, deluding the adventurous seafarer ever anew with empty hopes, and engaging him in enterprises which he can never abandon and yet is unable to carry to completion. Before we venture on this sea, to explore it in all directions and to obtain assurance whether there be any ground for such hopes, it will be well to begin by casting a glance upon the map of the land which we are about to leave, and to enquire, first, whether we cannot in any case be satisfied with what it contains -- are not, indeed, under compulsion to be satisfied, inasmuch as there may be no other territory upon which we can settle; and, secondly, by what title we possess even this domain, and can consider ourselves as secured against all opposing claims. (p 258)This is a language not only of adventure and discovery, but also of conquest and colonialism. Kant puts himself in the role of a colonial captain who is preparing for settlement and who is much concerned about the "title" to the territories explored so far. This language recurs when later he discusses the limits of reason, which mustn't extend itself beyond the field of possible experience:
... inscribing its nihil ulterius on those Pillars of Hercules which nature herself has erected in order that the voyage of our reason may be extended no further than the continuous coastline of experience itself reaches -- a coast we cannot leave without venturing upon a shoreless ocean which, after alluring us with everdeceptive prospects, compels us in the end to abandon as hopeless all this vexatious and tedious endeavour. (p. 362)Again, in the discussion of the paralogism of reason, Kant warns against taking even a single step beyond the realm of sense perception:
For by such procedure we should [...] have entered into the field of noumena; and no one could then deny our right of advancing yet further in this domain, indeed of settling in it, and, should our star prove auspicious, of establishing claims to permanent possession. (p. 371)Passages like these raise the question to what extent Kant's philosophical endeavor was coloured by the historical experience of Columbus and Cook. I'm not suggesting that the former simply reflects the latter or replicates it in thought, but at least it seems certain that it was from such experiences that Kant borrowed the metaphors by which he envisoned it.
Considering this explicit modelling of philosophy on voyages of discovery and colonialism, might we not suggest that the critique of pure reason is also a critique of colonialism? I think we can, at least if we take critique to mean, not necessarily a negative appraisal, but rather a scrutiny of possibility. Rather than as an imperialist, he can more accurately be described as a cartographer, carefully mapping the bounds beyond which colonial ventures must fail. Far from advocating overseas empires beyond the realm of the sensible, Kant seeks to prove the illusory character of such advocacy.
Speaking of territory, the issue of sovereignty is of course close at hand. Kant's use of metaphors related to sovereignty and political struggles is perhaps most apparent in the Preface to the first edition of the Critique, where he describes metaphysics as "the Queen of all the sciences" (p. 8).
Her government, under the administration of the dogmatists, was at first despotic. But inasmuch as the legislation still bore traces of the ancient barbarism, her empire gradually through intestine wars gave way to complete anarchy; and the sceptics, a species of nomads, despising all settled modes of life, broke up from time to time all civil society. (p. 9)In addition to nomadic skeptics, the queen's empire is also threatened by the plebs of common experience ("dem Pöbel der gemeinen Erfahrung", unhappily translated as "vulgar origins in common experience", p. 9).
In relation to this queen, Kant comes forward as an advocate of constitutional monarchy. Her realm is defended against nomads and plebs, but at the same time her power is circumscribed by the "tribunal" of critique, as befits "the matured judgment of the age, which refuses to be any longer put off with illusory knowledge" (p. 10).
It is a call to reason to undertake anew the most difficult of all its tasks, namely, that of self-knowledge, and to institute a tribunal which will assure to reason its lawful claims, and dismiss all groundless pretensions, not by despotic decrees, but in accordance with its own eternal and unalterable laws. This tribunal is no other than the critique of pure reason. (p. 10)The monarchy, then, mustn't be despotic. As befits an enlightened age, the precise reach of monarchial power must be prescribed by critique. Kant's metaphors even suggest that "revolution" might be a way to establish this desired form of monarchy:
This attempt to alter the procedure which has hitherto prevailed in metaphysics, by completely revolutionising it in accordance with the example set by the geometers and physicists, forms indeed the main purpose of this critique of pure speculative reason. (p. 26)Looking at passages like this, it feels like it wouldn't be impossible to extract an entire political philosophy from the Critique. To read a political message into it would probably go against Kant's own intentions (or wouldn't it?). Still, I can't help marvelling at the extent to which Kant, in his use of metaphors, provides a kind of sketch or map of the issues and concerns of his own historical situation, that of the 18th century, reproducing them as philosophical concerns in the mirror world of his system.
Kant, Immanuel (1929) Critique of Pure Reason (tr. Norman Kemp Smith), e-version prepared by Stephen Palmquist and placed in the Oxford Text Archive in 1985; http://staffweb.hkbu.edu.hk/ppp/cpr/toc.html(accessed 2017-01-14)