“Find a fraction which, multiplied by itself, shall give 6, or… find the square root of 6. This can be shown to be an impossible problem; for it can be shown that no fraction whatsoever multiplied by itself, can give a whole number, unless it be itself a whole number disguised in a fractional form, such as 4⁄2 or 21⁄3. To this problem, then, there is but one answer, that it is self-contradictory. But if we propose the following problem,—to find a fraction which, multiplied by itself, shall give a product lying between 6 and 6 + a; we find that this problem admits of solution in every case. It therefore admits of solution however small a may be… as small as you please.”
...there is such a thing as the square root of 6, and it is denoted by √<span style="text-decoration: overline">6</span>. But we do not say we actually find this, but that we approximate to it.
The Differential and Integral Calculus (1836)
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Augustus De Morgan 41
British mathematician, philosopher and university teacher (… 1806–1871Related quotes

Thoughts and Glimpses (1916-17)

No. 166 (10 September 1711).
The Spectator (1711–1714)

"Understanding and Imagination in the Light of Nature"
Variant: The world which we perceive is a tiny fraction of the world which we can perceive, which is a tiny fraction of the perceivable world...
Context: Because the fact is, what blinds us to the presence of alien intelligence is linguistic and cultural bias operating on ourselves. The world which we perceive is a tiny fraction of the world which we can perceive, which is a tiny fraction of the perceivable world, you see. We operate on a very narrow slice based on cultural conventions. So the important thing, if synergizing progress is the notion to be maximized (and I think it's the notion to be maximized), is to try and locate the blind spot in the culture — the place where the culture isn't looking, because it dare not — because if it were to look there, its previous values would dissolve, you see. For Western Civilization that place is the psychedelic experience as it emerges out of nature.

Thomas Jefferson's First State of the Union Address (8 December 1801)
1800s, First Presidential Administration (1801–1805)

Lecture "Year of Distraction" http://www.youtube.com/watch?v=ChWXYNxUFdc, at 1:07.

Disme: the Art of Tenths, Or, Decimall Arithmetike (1608)

“Group identity can be fractionated right down to the level of the individual.”
12 Rules for Life: An Antidote to Chaos, Rule 11: Do not bother children when they are skateboarding