a. (sb.) [f. as prec. + -AL: see -ICAL.]
† 1. (In sense of Gr. θεωρητικός, L. theōrēticus.) Of or pertaining to contemplation, contemplative.
1616. Bullokar, Eng. Expos., Theoretical, that which belongeth to contemplation or inward knowledge of a thing.
1623. Cockeram, Theoreticall, belonging to studie or contemplation.
2. Of, pertaining or relating to theory; of the nature of or consisting in theory. Often opp. to practical.
a. 1652. J. Smith, Sel. Disc., vi. 207. They fall into great confusions in many theoretical matters of no small moment.
1700. C. Nesse, Antid. Armin. (1827), 99. The persons … had merely escaped … through a theoretical knowledge of the Lord.
1727–41. Chambers, Cycl., s.v. Theoretic, The sciences are ordinarily divided into theoretical, as theology, philosophy, &c., and practical, as medicine, law, &c.
1770. Cook, Voy. round World, II. x. (1773), 477. The theoretical arguments which have been brought to prove that the existence of a southern continent is necessary to preserve an equilibrium between the two hemispheres.
1830. Mackintosh, Eth. Philos., Wks. 1846, I. 177. In the strictly theoretical part his exposition is considerably fuller.
1860. Maury, Phys. Geog. Sea (Low), viii. § 381. These observations agree with the theoretical deductions.
1860. Abp. Thomson, Laws Th., § 129. 274. Judgments that relate to speculation only are called theoretical; those which refer to practice are practical.
b. That is such according to theory; existing only in theory, ideal, hypothetical.
1826. Henry, Chem., II. 699. The theoretical numbers not agreeing with the experimental results, which are those of Dr. John Davy.
1883. Sir N. Lindley, in Law Rep., 11 Q. B. Div. 556. The attachment was granted for something more than a mere theoretical contempt.
1883. Gilmour, Mongols, xvii. 204. A man … whose existence is evidently … theoretical.
3. a. Of the mind or intellectual faculties: Having the power of forming theories; speculative.
a. 1652. J. Smith, Sel. Disc., iv. 115. As for the mind and theoretical power.
1863. E. V. Neale, Anal. Th. & Nat., 117. The intuitions of space and time, and the conceptions of relation drawn from the theoretical reason.
b. Of persons: Addicted to theory; constructing or dealing with theories; speculative.
1840. Carlyle, Heroes, vi. (1872), 211. What is to be done?… a question which theoretical constitution-builders may find easy to answer.
1859. Darwin, Orig. Spec., i. (1860), 12. Doubts have been thrown on this principle only by theoretical writers.
1902. J. Denney, Death of Christ, iii. 121. The simplest preacher and the most effective is always the most absolutely theoretical.
B. sb. (pl.) Theoretical points or matters.
1860. H. B. Wilson, in Ess. & Rev., 181. It is … strange … to expect all ministers … to be of one opinion in theoreticals.
