Theme: Philosophy - Live for the moment.
18A. "We're done here. Please leave": YOU MAY GO NOW
30A. Lone source of local entertainment: ONLY GAME IN TOWN
45A. Eschew modern conveniences: LIVE OFF THE GRID
57A. Like the child of your first cousin, to you: ONCE-REMOVED. (still a first cousin)
56D. Modern-day carpe diem spelled out at the starts of 18-, 30-, 45- and 57-Across: YOLO. (you only live once)
Argyle here. Carpe diem and the day is Tuesday. If you are Bond, James Bond, then You Only Live Twice. I liked today's pairing of RANT AND RAVE and YOSEMITE SAM.
1. __ for the course: PAR
4. Proverb: ADAGE
9. Wire fence stickers: BARBS. Inventors had a field day with this type of fencing.
14. Winner of the most 2016 Olympic medals: USA. 46 golds, 37 silvers and 38 bronzes. 44-Across. Part of 14-Across: Abbr.: AMERica.
15. Prize founder: NOBEL
16. Accustom (to): INURE
17. __ Tin Tin: RIN. Yo, Rinny! But who was Sgt. Preston's dog? (No, not Tige.)
20. For mature viewers: RATED R
22. Foot prettifier, briefly: PEDI. (pedicure)
23. Miss. neighbor: ALA. (Alabama)
24. Grape-Nuts cereal brand: POST. Developed in 1897 by C. W. Post, no grapes or nuts were harmed in the making of this cereal.
26. Big Board letters: NYSE. (New York Stock Exchange)
33. Pop in a glass: SODA. Not the same as pop in his cups.
34. Wonder: AWE
35. Longtime name in Syrian leadership: ASSAD. Hafez al-Assad and his son, Bashar al-Assad.
36. Prereq for a lifeguard: CPR. (CardioPulmonary Resuscitation)
37. Fred Flintstone's boss: MR. SLATE
40. CBS logo: EYE
41. Yoga position: ASANA. Number of positions
43. Conservationist's prefix: ECO. (ecological interaction)
49. Worrisome grades: DEEs
50. Misplace: LOSE
51. Tennis do-over: LET
52. Open house offering: TOUR
54. Great suffering: MISERY
62. Great Lakes' __ Canals: SOO
63. Baseball legend Satchel: PAIGE. The Official Satchel Paige Home Page.
64. Dior skirt style: A-LINE
65. "__ the President's Men": ALL by Carl Bernstein and Bob Woodward.
66. Does' mates: STAGS
67. Cares for: TENDS
68. Sound on Old MacDonald's farm: MOO
1. Sound of a contented kitty: PURR
2. Great Wall setting: ASIA
3. Deliver a tirade: RANT AND RAVE
4. Sometime soon: ANY DAY
5. "Let's Make a Deal" selection: DOOR. Often three doors but what's behind them?
6. __ Dhabi: ABU
7. Emerald, e.g.: GEM
8. Slip by: ELAPSE
9. Texas city of 1.3 million, familiarly: BIG D. Dallas.
10. Consecrates with oil: ANOINTS
11. It may be unearned: RUN
12. Compadre: BRO. (Brother)
13. Clinch, with "up": SEW
19. Mythical Himalayan: YETI
21. Singer Fitzgerald: ELLA
24. Feline feet: PAWS
25. Brunch servings: OMELETS
27. Ill-tempered Looney Tunes character: YOSEMITE SAM
28. Persuaded: SWAYED
29. Week or rear add-on: ENDER. Better to have a weekender than a rear-ender.
30. "My bad!": "OOPSIE!"
31. Needlefish: GAR
32. Scottish denial: NAE
33. Nearly boil: SCALD. Nearly a repeat of yesterday.
37. Long March leader in 1930s China: MAO. Mao Zedong.
38. Tylenol target: ACHE
39. One may be stubbed: TOE
42. Retirement fund: NEST EGG
44. Belligerent god: ARES. Greek god of war, son of Zeus and Hera.
46. Chimney part: FLUE. Now is the time to have it checked before the heating season. PSA
47. Word processing category involving page dimensions: FORMAT
48. Moves smoothly: GLIDES
53. Lodes and lodes: ORES
54. Patch up: MEND
55. Hershey's caramel candy: ROLO. A treat for trick-or-treaters.
57. Black __: covert missions: OPS. (see 59-Down)
58. D.C. ballplayer: NAT. Washington Nationals.
59. Spy novel org.: CIA. (Central Intelligence Agency)
60. "¡Viva el matador!": "¡OLE!"
61. __ Scully, Dodger announcer for 67 seasons: VIN