104 



LETTERS ON TREES. 



ideas seem to vary, **the variation arises, not from a 

 different idea following the perception of the same 

 relations, but from the perception of seemingly the 

 same thing in different relations." Among other illus- 

 trations of this observation, he gives that placed at the 

 head of this letter, — alleging also that what holds true 

 of the perceptions that come to us through the senses^ 

 is true also of the perceptions derived through the 

 reason, 



2. Comparing, then, our subject — the Tree — to this 

 octagonal building, and the details regarding it which 

 have engaged our attention, to the several sides of this 

 building, let us consider, before we finally take leave 

 of it, whether we have examined it in all its relations, 

 — whether we have indeed gone completely round it, 

 and looked at its every side. 



3. And that we may be well assured that we have 

 done so, let us inquire what account other observers 

 have given of it. We may not find, perhaps, that any 

 one has examined it exactly as we have done, — or 

 rather with the view of discovering whether these par- 

 ticular relations obtain among its several parts which 

 we have seen or fancied to hold. But I have no doubt 

 we shall find that every face and side of the building 

 has been seen by some one or more observers ; and our 

 business will be to see whether or how far the descrip- 

 tions given of it by others agree with or differ from 

 ours. If they agree, well and good. The coincidence 



