Theoretical scientific knowledge is perhaps open to Hume's critique, but for technology, which is the practical application of the 'scientific' form of knowledge, all that matters is whether such knowledge is functionally valid or not. All human technology ever developed (and even non-human technology, to the extent that it exists) is a manifestation of functionally valid knowledge. Its successful functionality is all the validation required: whether it is "the same table" or not, it still serves as a table (and one that is the same in all functionally critical respects, such as its dimensions).