8 ideas
| 21597 | Logical connectives have the highest precision, yet are infected by the vagueness of true and false [Russell, by Williamson] |
| Full Idea: Russell says the best chance of avoiding vagueness are the logical connectives. ...But the vagueness of 'true' and 'false' infects the logical connectives too. All words are vague. Russell concludes that all language is vague. | |
| From: report of Bertrand Russell (Vagueness [1923]) by Timothy Williamson - Vagueness 2.4 | |
| A reaction: This relies on the logical connectives being defined semantically, in terms of T and F, but that is standard. Presumably the formal uninterpreted syntax is not vague. |
| 9051 | Since natural language is not precise it cannot be in the province of logic [Russell, by Keefe/Smith] |
| Full Idea: Russell takes it that logic assumes precision, and since natural language is not precise it cannot be in the province of logic at all. | |
| From: report of Bertrand Russell (Vagueness [1923]) by R Keefe / P Smith - Intro: Theories of Vagueness §1 | |
| A reaction: I find this view congenial. It seems to me that the necessary prelude to logic is to do everything you can to eliminate ambiguity and vagueness from the sentences at issue. We want the proposition, or logical form. If there isn't one, forget it? |
| 9054 | Vagueness is only a characteristic of representations, such as language [Russell] |
| Full Idea: Vagueness and precision alike are characteristics which can only belong to a representation, of which language is an example. | |
| From: Bertrand Russell (Vagueness [1923], p.62) | |
| A reaction: Russell was the first to tackle the question of vagueness, and he may have got it right. If we are unable to decide which set an object belongs in (red or orange) that is a problem for our conceptual/linguistic scheme. The object still has a colour! |
| 15119 | Aristotelian explanation by essence may need to draw on knowledge of other essences [Aristotle, by Koslicki] |
| Full Idea: From Aristotle's biology we learn that a successful scientific explanation of the necessary (but non-essential) features of one type of phenomenon (e.g. camels) my require appeal to facts about the essences of other types of phenomena (stomachs). | |
| From: report of Aristotle (The History of Animals [c.344 BCE]) by Kathrin Koslicki - Essence, Necessity and Explanation 13.4 |
| 1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
| Full Idea: Archelaus was the first person to say that the universe is boundless. | |
| From: report of Archelaus (fragments/reports [c.450 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 02.Ar.3 |
| 23302 | Plants have far less life than animals, but more life than other corporeal entities [Aristotle] |
| Full Idea: The genus of plants, whilst it is devoid of life compared with an animal, is endowed with life as compared with other corporeal entities. In the sea there are certain objects which one would be at a loss to determine whether they be animal or vegetable. | |
| From: Aristotle (The History of Animals [c.344 BCE], 588b09) | |
| A reaction: It seems that Aristotle takes life to come in degrees, assessed by the amount of physical vitality observed. This seems to make lambs more alive than sheep, which isn't very plausible. This is part of his 'gradualist' view of nature. |
| 5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |
| Full Idea: Archelaus wrote that life on Earth began in a primeval slime. | |
| From: report of Archelaus (fragments/reports [c.450 BCE]) by Malcolm Schofield - Archelaus | |
| A reaction: This sounds like a fairly clearcut assertion of the production of life by evolution. Darwin's contribution was to propose the mechanism for achieving it. We should honour the name of Archelaus for this idea. |
| 23301 | There is a gradual proceeding from the inanimate to animals, with no clear borderlines [Aristotle] |
| Full Idea: Nature proceeds little by little from things lifeless to animal life so that it is impossible to determine the exact line of demarcation, nor on which side an intermediate form should lie. ...In plants there is a continuous ascent towards the animal. | |
| From: Aristotle (The History of Animals [c.344 BCE], 588b04) | |
| A reaction: This in itself should have alerted medieval Christians to the problematic nature of the idea that animal species were divinely created. |