a. [f. THOUGHT1 + -LESS.] That is without thought, in various senses: the opposite of THOUGHTFUL.
1. Not taking thought, acting without thought or reflection; unreflecting, heedless, imprudent.
1592. Kyd, Sp. Trag., IV. i. 40. Nor thinke I thoughtles thinke vpon a meane, To let his death be vnreueng’d at full.
1611. Florio, Inpensierato, thoughtlesse, carelesse.
a. 1704. T. Brown, Sat. agst. Woman, 39. Weak curses … For thoughtless crimes, which come out of thy kind.
1736. Butler, Anal., I. ii. Wks. 1874, I. 42. Youth may be alleged as an excuse for rashness and folly, as being naturally thoughtless.
1849. B. Taylor, in Life & Lett., I. vii. 149. I shall neither be rash nor thoughtless.
b. With of or dependent clause: Not thinking; unmindful, forgetful; hecdless, careless; unsuspecting. Now rare.
1615. Chapman, Odyss., V. 19. He … Finds you so thoughtlesse of him, and his birth.
16[?]. Rogers (J.). Without remorse for the past, and thoughtless of the future.
1697. Dryden, Virg. Georg., III. 668. A Snake … Leaving his Nest … thoughtless of his Eggs.
1725. Pope, Odyss., IV. 716. The Royal guest, Thoughtless of ill, accepts the fraudful feast.
1742. Young, Nt. Th. IV. 365. Men homage pay to men, Thoughtless beneath whose dreadful eye they bow.
† c. Free from care or anxiety. Also transf. Obs.
1742. Gray, Eton Coll., v. The thoughtless day, the easy night.
1764. Goldsm., Trav., 255. So blest a life these thoughtless realms display.
1789. Blake, Songs Innoc., Night, 17. They look in every thoughtless nest.
d. Wanting in consideration for others; inconsiderate.
1794. Blake, Songs Exper., Fly, 3 Little fly, Thy summer’s play My thoughtless hand Has brush’d away.
Mod. It was very thoughtless of you to disturb her.
2. Deficient in or lacking thought; not given to thinking; stupid, senseless, dull-witted; destitute of ideas. Now rare.
1682. Dryden, Mac Flecknoe, 26. Shadwell never deviates into sense…, his goodly fabric … seems designed for thoughtless majesty.
1714. Pope, Epil. Jane Shore, 7. As a blockhead rubs his thoughtless skull, And thanks his stars he was not born a fool.
1879. B. Taylor, Stud. Germ. Lit., 194. He was an earnest thinker in a thoughtless time.
† b. Of inanimate things: Devoid of thought.
1691–8. Norris, Pract. Disc. (1711), III. 22. Bodies have no Thought, therefore they produce none:… for how can a thoughtless Principle produce a Thought?
c. 1705. Berkeley, Commonpl. Bk., Wks. 1871, IV. 469. Extension to exist in a thoughtless thing (or rather in a thing void of perception …), is a contradiction.
