The second principle, however, is that of potentiation by dilution - including dilution to a point where you can be pretty sure (even in 1790) that nothing is left being the most potent of all.
There is pretty good evidence that ultra high dilution of substances in water leave a very specific signature.
By ultra high, I mean below the Avogadro number, so ofter impugned by homeo-skeptics.
See my previous post here
Does this mean that homeopathy is proved? Absolutely not, but to claim that the potentiation technique is bogus I think it's not reflecting the existing evidence. Including that of Montagnier recent experiments, although not conclusive.
Finally, to sound like a broken record, I need to remind that almost all homeopathic remedies
come in dilutions where the active substance is definitely present, and therefore potentially active. All decimal dilutions from D1 to D24 and all centesimal dilutions from C3 to C12.
Once again modern, Rekeweg-ian, homeopathy uses extensively these dilutions.
A valid point, but what the researcher might have meant is 'we know cannot work'.
Of course it can, if an active substance is detectable. It doesn't even contradict our current biochemical paradigm!
Purporting homeopathy as a practice based on undetectable substances and implausible principles is fallacious. Recent experiments such as those linked above would seem to make it more plausible, if anything.
The topic is controversial and there is some valid criticism, but I find it pointless to keep beating the dead horse of "no substance".